Distributed video encoder and decoder and distributed video decoding method

Abstract

A distributed video encoder and decoder and a distributed video decoding method using adaptive quantization are provided. Adaptive quantization is performed at the time of encoding and decoding so that limited resources and information can be efficiently used, and a predetermined bit which is previously defined is included in a position of a bit which does not need to be transmitted for channel coding, thereby improving a bit rate-distortion performance as a whole.

1. A distributed video encoder, comprising:
 a key picture encoding unit which encodes a key picture and outputs an encoded key picture; 
 a block unit dividing unit which divides a WZ picture into predetermined coding units; 
 an adaptive quantization processing unit which determines quantization strength of each area using coding unit information; 
 an adaptive quantization unit which performs quantization of the coding unit information output from the block unit dividing unit with the determined quantization strength of each area; and 
 a channel code encoding unit which channel-codes the quantized coding unit information in a bit plane unit and outputs parity data, 
 wherein the distributed video encoder is configured to identify quantization discard positions based on the quantization strength of each area and fill the quantization discard positions with a predetermined bit value. 
 
     
     
       2. A distributed video decoder, comprising:
 a key picture decoding unit which decodes an encoded key picture and outputs a decoded key picture; 
 a side information generating unit which generates side information using the decoded key picture; 
 an adaptive dequantization processing unit which determines quantization strength of each area using quantization strength information which is shared with an encoder; 
 a channel code decoding unit which identifies quantization discard positions and estimates a quantized value using the side information generated by the side information generating unit, the quantization strength determined by the adaptive dequantization strength processing unit, parity data input from the outside and the quantization discard positions filled with a predetermined bit value based on the quantization strength of each area; 
 an adaptive dequantization unit which computes a dequantized value using the quantization strength of each area and the estimated quantized value; and 
 a video reconstruction unit which reconstructs a WZ picture using the computed dequantized value, and the side information. 
 
     
     
       3. The distributed video decoder of  claim 2 , wherein the quantization strength information comprises the side information input from the side information generating unit. 
     
     
       4. A distributed video decoding method, comprising:
 receiving parity data and an encoded key picture; 
 decoding the encoded key picture and outputting a decoded key picture; 
 generating side information using the decoded key picture; 
 determining quantization strength of each area using quantization strength information which is shared with an encoder; 
 estimating a quantized value using the side information, the quantization strength, the parity data and the quantization discard positions filled with a predetermined bit value based on the quantization strength of each area 
 computing a dequantized value using the quantization strength of each area and the estimated quantized value; and 
 reconstructing a WZ picture using the computed dequantized value and the side information. 
 
     
     
       5. The distributed video decoding method of  claim 4 , wherein the quantization strength information comprises the side information input from the side information generating unit.